A wind turbine blade with a fairing

Abstract

The present invention relates to a method of manufacturing a fibre-reinforced part ( 50 ) for a wind turbine blade ( 10 ). The method comprises the steps of providing a first layer ( 57 ), the first layer comprising a thermoplastic elastomer; arranging a second layer ( 56 ) on top of the first layer ( 57 ), the second layer ( 56 ) comprising a fibre material; and heating the first layer ( 57 ) and the second layer ( 56 ) to a temperature of 35-90° C. The heated first and second layers are then contacted with a liquid epoxy resin or a liquid mixture of epoxy resins. Subsequently, the epoxy resin is cured to adhere the first layer ( 57 ) to the second layer ( 56 ) to obtain the fibre-reinforced part.

1 . A method of manufacturing a fibre-reinforced part ( 50 ) for a wind turbine blade ( 10 ), the method comprising the steps of:
 providing a first layer ( 57 ), the first layer comprising a thermoplastic elastomer;   arranging a second layer ( 56 ) on top of the first layer ( 57 ), the second layer ( 56 ) comprising a fibre material;   heating the first layer ( 57 ) and the second layer ( 56 ) to a temperature of 35-90° C.;   contacting the heated first and second layers with a liquid epoxy resin or a liquid mixture of epoxy resins; and   curing the epoxy resin or mixture of epoxy resins to adhere the first layer ( 57 ) to the second layer ( 56 ) to obtain the fibre-reinforced part.   
     
     
         2 . A method according to  claim 1 , wherein the heating step comprises heating the first layer ( 57 ) and the second layer ( 56 ) to a temperature of 40-80° C., preferably 50-70° C. 
     
     
         3 . A method according to  claim 1 , wherein the epoxy resin has an epoxy equivalent of 150-200. 
     
     
         4 . A method according to  claim 1 , wherein the method further comprises a step of contacting the heated first and second layers with a hardener, preferably an amine curing agent, prior to the step of curing the epoxy resin or mixture of epoxy resins. 
     
     
         5 . A method according to  claim 4 , wherein the hardener has an amine value of 400-600 mg KOH/g. 
     
     
         6 . A method according to  claim 1 , wherein the step of curing comprises forming crosslinks between the epoxy resin or mixture of epoxy resins and the first layer. 
     
     
         7 . A method according to  claim 1 , wherein the first layer consists of a thermoplastic elastomer. 
     
     
         8 . A method according to  claim 1 , wherein the thermoplastic elastomer is a thermoplastic polyurethane. 
     
     
         9 . A method according to  claim 1 , wherein the first layer has a thickness of 0.3-3 mm, preferably 0.75-1.5 mm. 
     
     
         10 . A method according to  claim 1 , wherein the step of curing the epoxy resin or mixture of epoxy resins is carried out at a temperature of at least 60° C., preferably at least 70° C., more preferably at least 80° C. 
     
     
         11 . A method according to  claim 1 , wherein the step of contacting the heated first and second layers with a liquid epoxy resin or a liquid mixture of epoxy resins is carried out by vacuum assisted resin transfer moulding. 
     
     
         12 . A method according to  claim 1 , wherein the fibre-reinforced part is a fairing or an erosion shield for a leading edge of the wind turbine blade. 
     
     
         13 . A method according to  claim 1 , wherein the heating step comprises heating the first layer ( 57 ) and the second layer ( 56 ) to a temperature of 40-59° C., preferably 40-55° C. 
     
     
         14 . A method according to  claim 1 , wherein the epoxy resin is a liquid at a temperature of 25° C. and a pressure of 1 atm. 
     
     
         15 . A wind turbine blade ( 10 ) extending along a longitudinal axis (L) from a root ( 16 ) to a tip ( 14 ), the wind turbine blade ( 10 ) comprising a root region ( 30 ) and an airfoil region ( 34 ) with the tip ( 14 ), the wind turbine blade ( 10 ) comprising a chord line extending between a leading edge ( 18 ) and a trailing edge ( 20 ) thereof, the wind turbine blade ( 10 ) comprising an aerodynamic exterior blade surface ( 22 ) including a pressure side and a suction side, wherein the wind turbine blade comprises a fibre-reinforced part obtainable by the method of  claim 1 . 
     
     
         16 . A wind turbine blade according to  claim 15 , wherein the fibre-reinforced part is a fairing ( 50 ) or an erosion shield, wherein the fairing ( 50 ) or erosion shield extends along the longitudinal axis (L) and along a fairing profile ( 51 ) terminating at a first fairing lip ( 52 ) of the fairing ( 50 ) or erosion shield and at a second fairing lip ( 53 ) of the fairing ( 50 ) or erosion shield, the fairing ( 50 ) or erosion shield comprising an exterior fairing surface ( 54 ) positioned exteriorly relative to the fairing profile ( 51 ), an interior fairing surface ( 55 ) positioned interiorly relative to the fairing profile ( 51 ), and one or more fibre-reinforced layers ( 56 ) extending from the first fairing lip ( 52 ) to the second fairing lip ( 53 ) and along the longitudinal axis (L), wherein the one or more fibre-reinforced layers ( 56 ) forms part of a plurality of layers further including an exterior erosion-resistant elastomer layer ( 57 ) forming at least a portion of the exterior fairing surface ( 54 ) and being configured for defining at least part of the leading edge ( 18 ) of the wind turbine blade ( 10 ), wherein the exterior erosion-resistant elastomer layer ( 57 ) is preferably made of polyurethane, wherein the fairing ( 50 ) or erosion shield further comprises a cured first resin ( 58 ) binding the erosion-resistant elastomer layer and the one or more fibre-reinforced layers ( 56 ) together. 
     
     
         17 . A method of manufacturing a wind turbine blade ( 10 ) with a fibre-reinforced part, the method comprising the steps of:
 providing a fibre-reinforced part in accordance with the method according to  claim 1 ;   separately providing a structural blade body ( 40 ); and   manufacturing the wind turbine blade ( 10 ) by bonding the fibre-reinforced part to the structural blade body ( 40 ), preferably such that the fibre-reinforced part defines at least part of either the leading edge ( 18 ) of the wind turbine blade ( 10 ) or the trailing edge ( 20 ) of the wind turbine blade ( 10 ).